Stellar designation

Designations of stars (and other celestial bodies) is mediated by the International Astronomical Union (IAU). Many of the star names in use today were inherited from the time before the IAU existed. Other names, mainly for variable stars (including novae and supernovae), are being added all the time.

Approximately 10,000 stars are visible to the naked eye. Pre-modern catalogues listed only the brightest of these. Hipparchus in the 2nd century BC enumerated about 850 stars. Johann Bayer in 1603 listed about twice this number. Only a minority of these have proper names; all others are designated by numbers from various catalogues. Only in the 19th century did star catalogues list the naked-eye stars exhaustively. The most voluminous modern catalogues list on the order of a billion stars, out of an estimated total of 200 to 400 billion in the Milky Way.

Proper names

Several hundred of the brightest stars have traditional names, most of which derive from Arabic, but a few from Latin.